Scientists in Netherlands have mentioned that vitamin K could help fight Covid-19. vitamin K's role is to stop your blood when you get bleeding. vitamin K is in spinach, broccoli, green vegetables, blueberries. In this article, there is a comment about Japanese Natto. Natto is also contained a lot of vitamin K. Two month ago, Natto in a supermarket around Tokyo hadn't been out of stock. Because of this reason. I didn't interested in the situation but Kimchi includes vitamin K as well. The points common to both countries are a few death cases. so I also think vitamin K could help fight Covid-19. I want to know the result of this research someday.